How to filter Spark dataframe if one column is a member of another column

Question

I have a dataframe with two columns(one string and one array of string):

root
 |-- user: string (nullable = true)
 |-- users: array (nullable = true)
 |    |-- element: string (containsNull = true)

How can I filter the dataframe so that the result dataframe only contains rows that user is in users?

Answer 1

Quick and simple:

import org.apache.spark.sql.functions.expr

df.where(expr("array_contains(users, user)")